When vision is severely impaired...
...and can no longer be corrected adequately with prescription glasses or contact lenses, basic everyday skills are lost.
According to the German "Kuratorium Gutes Sehen”, an initiative for good vision, one in five people aged 70 and above have such poor vision that they can no longer manage with standard prescription glasses. With poor vision, opportunities to participate socially decrease and people’s sphere of action is greatly reduced. Advances in technology have, however, created new opportunities to make best use of the patients’ residual vision. Special optical and electronic magnifying devices can help enhance vision. Low vision solutions are now widely available for personal use and for use – for younger patients – in the workplace, which can be reconfigured as people’s needs necessitate.
Electronic magnifying devices
In addition to optical magnifiers, the number of electronic magnification systems available is increasing. The advantage of these devices is that visually impaired people can increase contrast while also adjusting the magnification to suit their individual requirements.
Electronic magnifying devices include:
Electronic vision enhancement systems offer high magnification levels. With higher magnification, however, very little information fits on a screen. Often only a few words can be visualised on the screen, and long words cannot be displayed at all. Starting to use electronic vision enhancing systems is recommended from as soon as moderate magnification is needed. Judging from experience, it is ideal to start with magnification strengths between 6x and 12x.
As the visual acuity decreases further – often rather slowly – patients can increase magnification step by step to continue reading. In this way, they can gradually get used to the various difficulties that arise with higher magnification levels – usually with great success!
Advantages of video magnifiers:
Handheld video magnifiers are small, lightweight, portable electronic magnifiers that resemble smartphones or tablet computers. They offer almost the same features as traditional desktop video magnifiers, but must be moved across the reading material. Handheld video magnifiers are available in many different magnification ranges and enable patients to change brightness, colour and contrast settings to suit individual preferences, which is another major advantage. When adjusting the image size, however, patients must be aware that the field of view will decrease as magnification increases. Handheld video magnifiers are ideal entry-level devices in the field of electronic vision enhancing systems. Their (between 4.3-inch and 7-inch) screens are substantially smaller than those of desktop video magnifiers, but 2-3 times larger than those of modern digital cameras.
Handheld video magnifiers are powered by rechargeable batteries. While some models enable patients to write underneath the device for a short time, others offer a distance reading function which enables the magnification of near and distant objects. Some handheld video magnifiers can also be connected to a television. Their “snapshot” function is another comfortable feature and enables patients to save one or several images (e.g. of a train schedule) for later viewing. This feature is also convenient when patients need to read information which is difficult to access on, say, price labels in supermarkets or bus schedules displayed well above eye level.
When looking at desktop video magnifiers and handheld video magnifiers, it should be noted that the latter cannot replace a traditional desktop device. It can, however, be a huge help with mobility! Handheld video magnifiers are fitted and dispensed in the same way as desktop systems. Having taken the patient’s history and determined the magnification required, the handheld video magnifier is set to the relevant magnification power. With an appropriate corrective plus lens, the patient should then be able to read newsprint-sized text. In the event of impaired contrast vision, patients can choose from different colour modes to find the one that suits them best. Handheld video magnifiers are ideal entry-level devices in the field of electronic magnifiers – for patients and eye care professionals alike.
The range of video magnifiers is continuously expanding. They are particularly useful for patients with severe sight impairment, enabling them to maintain their reading ability.
Patients should be made familiar with these devices early on, i.e. when requiring only moderate magnification. In this way, they can gradually get used to the difficulties that arise as more magnification is needed with the worsening of their sight impairment.
The benefits of electronic assistive devices and traditional optical and non-optical low vision aids must be carefully compared to find out whether the electronic devices really make a difference to the life of a visually impaired person. Optimising lighting conditions or fitting patients with illuminated magnifiers, high addition spectacles or telescopic systems may sometimes be the better choice for an individual patient.
For more information on video magnifiers click here.